1. Field of the Invention
The present invention relates to a backlight, and more particularly, to a backlight driving apparatus which is capable of simplifying a circuit configuration for driving of a plurality of light emitting diode arrays and making the current balance of the light emitting diode arrays uniform.
2. Discussion of the Related Art
Generally, a liquid crystal display (LCD) device is comprised of an LCD panel which includes a plurality of liquid crystal cells arranged in a matrix configuration, and a plurality of control switches to switch video signals supplied to the respective liquid crystal cells; and a backlight unit to emit light to the LCD panel. The LCD device displays desired images on a screen by controlling the transmittance of light.
The backlight unit is in trend of miniaturization, thin profile and lightness in weight. Following this trend of backlight unit, a light-emitting diode (LED) replaces a fluorescent lamp since the LED is advantageous in power consumption, weight and luminance.
FIG. 1 shows a schematic view of a general backlight driving apparatus.
Referring to FIG. 1, the general backlight driving apparatus includes a plurality of light emitting diode (LED) arrays 101 to 10n, and a plurality of power sources 201 to 20n for generating a plurality of driving currents to drive the LED arrays 101 to 10n, respectively.
The power sources 201 to 20n generates the driving current using an external input voltage Vin in response to control signals from a plurality of controllers (not shown), respectively.
Each of the LED arrays 101 to 10n includes a plurality of LEDs (L1 to Lm) connected in series between each of the power sources 201 to 20n and a ground voltage source.
The LEDs (L1 to Lm) of each LED array are lighted by current supplied from each of the power sources 201 to 20n. 
The above-mentioned general backlight driving apparatus is disadvantageous in that the plurality of power sources 201 to 20n and the plurality of controllers must be provided to drive the plurality of LED arrays 101 to 10n, respectively, resulting in a complexity in circuit configuration and an increase in cost.
Moreover, in the general backlight driving apparatus, there is no uniformity in the balance of currents which are supplied from the plurality of power sources 201 to 20n to the plurality of LED arrays 101 to 10n, respectively.